Robert P. Marshall with a reproduction of an 1822 map by Stephen F. Austin. He believes he’s located the site of the Battle of Medina.

Robert P. Marshall with a reproduction of an 1822 map by Stephen F. Austin. He believes he’s located the site of the Battle of Medina.

Photo: Jerry Lara, San Antonio Express-News

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A commmercial reproduction of a 1822 map of Texas by Stephen F. Austin is seen Thursday, March 1, 2012. Robert P. Marshall, a retired petroleum geologist, believes he has found the true site of the 1813 Battle of Medina.

A commmercial reproduction of a 1822 map of Texas by Stephen F. Austin is seen Thursday, March 1, 2012. Robert P. Marshall, a retired petroleum geologist, believes he has found the true site of the 1813 Battle

Robert P. Marshall with a reproduction of an 1822 map by Stephen F. Austin. He believes he’s located the site of the Battle of Medina.

Robert P. Marshall with a reproduction of an 1822 map by Stephen F. Austin. He believes he’s located the site of the Battle of Medina.

Photo: Jerry Lara, San Antonio Express-News

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The Battle of Medina

The Battle of Medina

Photo: Mark Blackwell

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Re-enactors fire a musket volley during a recreation of the Battle of Medina last August. The Battle of Medina was fought on Aug. 18, 1813, but the exact location remains a mystery lost to history.

Re-enactors fire a musket volley during a recreation of the Battle of Medina last August. The Battle of Medina was fought on Aug. 18, 1813, but the exact location remains a mystery lost to history.

Photo: BILLY CALZADA, BILLY CALZADA / Gcalzada@express-news.net

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Re-enactors Eric Teniente (from left), Edward Teniente and Jorge Chavez wear garb of Tejanos of the Republican Army of the North during a recreation of the Battle of Medina last August. The Battle of Medina was fought on Aug. 18, 1813, but the exact location remains a mystery lost to history.

Re-enactors Eric Teniente (from left), Edward Teniente and Jorge Chavez wear garb of Tejanos of the Republican Army of the North during a recreation of the Battle of Medina last August. The Battle of Medina was

The state's 1936 Battle of Medina marker at the southeast corner of U.S. 281 South and Martinez Losoya Road has been badly defaced. The word "Medina" has been scratched out, and the bronze wreath and star removed. Historians now believe the marker may be about six miles north of the site of the heaviest fighting from the Aug. 18, 1813 battle — the deadliest in Texas history.

The state's 1936 Battle of Medina marker at the southeast corner of U.S. 281 South and Martinez Losoya Road has been badly defaced. The word "Medina" has been scratched out, and the bronze wreath and star

A retired petroleum geologist with a love of history says he's found the long-lost site of the deadliest battle ever fought on Texas soil.

Though he's yet to persuade scholars, Robert P. Marshall has intrigued some and flustered others with his 40-page report declaring the Battle of Medina site “has been located!”

Today is Texas Independence Day, the anniversary of the March 2, 1836, signing of the Texas Declaration of Independence. But some Texas history fans focus their energy on the first Texas republic, created in a revolt against Spain nearly 200 years ago and overturned in the lopsided Battle of Medina.

“I've spent many hours doing the research. My wife has said it's been an obsession,” said Marshall, 74, of San Antonio.

Kay Hindes, San Antonio's city archaeologist, said Marshall has presented “tantalizing evidence” but hasn't produced archaeological proof needed to have a historical marker placed.

“We just have to have incontrovertible evidence,” said Hindes, who has searched for the site for years.

Some 1,400 Anglos, Tejanos and American Indians with the Republican Army of the North were routed in the four-hour battle by the Spanish Royal Army somewhere south of San Antonio on Aug. 18, 1813. The first republic of Texas was crushed as 800 to 1,000 rebels were killed in battle. Hundreds more were executed.

Marshall, a Huntsville native and fifth-generation Texan, has lived in Texas most of his life. In 2009, when he first read details of the battle, he began to question old theories about where it was fought.

“I've taken the same approach as a geologist trying to find an oilfield, using facts and mathematics,” he said.

An 1822 map by Stephen F. Austin was one of the key maps Marshall studied before concluding that the battle's main engagement was fought along the camino que cortaba, predecessor to today's Old Pleasanton Road. Using diary accounts from battle participants and others who traveled through the area, he identified a site about two miles east of a battle marker placed in 2005 at Bruce and Applewhite roads.

Dan Arellano, a historian in Austin also in search of the site, has disputed Marshall's findings. Arellano has argued that troops in the battle were on another road that would have placed it west or northeast of the site Marshall identified.

But José M. Peña, another Austin historian, said he and Marshall reached similar findings two years ago, even though the two have never spoken. Peña, 80, said the site he identified is just west of Marshall's.

More Information

Two-day festival

A festival to mark Texas Independence Day will take place Saturday and Sunday, 10 a.m. to 5 p.m., at Washington-on-the-Brazos State Historic Site, 20 miles northeast of Brenham.

While the Alamo was under siege, other Texians convened at Washington-on-the-Brazos on March 1, 1836, to decide the future of Texas. The delegates worked through the night to draft and sign a declaration of "a free and independent Republic of Texas." As we observe Texas Independence Day, here are some facts worth knowing:

• Texas Independence Day celebrates the declaration of a sovereign republic, free from Mexican rule. In 1845, Texas was annexed by the United States as the 28th state.

• The Burnet Flag was the first flag of the new republic, proposed by then-President David G. Burnet as a blue flag with a single gold star and adopted in 1836. The current state flag was created in 1839.

• The original, hand-written Texas Declaration of Independence was taken by William H. Wharton to the U.S. State Department in Washington after it was signed. It was returned to Texas in 1896. A reproduction is on display in the Texas Capitol.

• Of the 59 signers the Texas Declaration of Independence, only two — José Francisco Ruiz and José Antonio Navarro — were native Texans, according to the Star of the Republic Museum. The other 57 were from 12 states and five foreign countries — Mexico, Canada, England, Scotland and Ireland. Only 10 had lived in Texas longer than six years, and 15 had moved to the state less than a year earlier.

• The San Jacinto Monument, LaPorte, marks the site where Gen. Sam Houston and his troops defeated Santa Anna and won independence from Mexico on April 21, 1836. That historic site now draws more than 250,000 visitors a year.

“I came basically to the same conclusion. Not in the same spot, but very close to it,” Peña said.

In his report, Marshall said the battle's impact on a young Spanish lieutenant, Antonio López de Santa Anna, may have fueled his overconfidence in his 1836 Texas campaign as the Mexican generalissimo. Santa Anna's decision to divide his force after a costly victory at the Alamo contributed to his defeat at San Jacinto, Marshall wrote.

Although at least a dozen sites have been suggested as the location of the main engagement, no artifacts ever have been conclusively linked to the Battle of Medina, Hindes said. But she didn't dismiss Marshall's theories. It may take more careful research to find the true site, so artifacts can be professionally unearthed, she said.

“Sometimes, a fresh perspective is useful,” Hindes said.

Marshall believes evidence may never be found that satisfy archaeologists. Human bones from the battle that were sun-bleached for nine years before being buried have likely dissolved in the acidic sandy soil. Ordnance has sunk too deep for today's metal detectors to find, he said.

His report describes oral accounts from property owners about iron and lead balls that he says support his finding. He's selling his report in exchange for donations of $20 or more, to fund for a new historic marker. Orders may be sent to his address, 13110 Hunters Spring St., San Antonio 78230.

“As far as I'm concerned, the site has been found,” he said. “Artifacts are a supplement to history. They are not what defines history.”